1. Technical Field
The present invention relates to a technique for managing an ink cartridge installed in a printer, or for managing another object used in an electronic instrument.
2. Related Art
In a conventional ink cartridges (including toner cartridges; the same hereinafter) for installation in a printer, a memory IC or other writable storage device is sometimes provided (see Japanese Laid-Open Patent Application Publication No. 2003-216710 and Japanese Laid-Open Patent Application Publication No. 2005-115640, for example). A serial number, manufacturer ID, and other information of the ink cartridge, for example, are recorded in the storage device. Information indicating the ink level is also sometimes written in the storage device by the printer in which the ink cartridge is installed. By using these items of information, the printer can manage the ink level or the identification of each ink cartridge.
However, the writable storage device is an electronic component, and is therefore generally expensive, and this high cost hinders efforts to lower the cost of the ink cartridge. There is therefore a need for a technique of managing individual ink cartridges without mounting a writable storage device. The need for such a technique is not limited to use in ink cartridges, and the same need exists for a technique of managing printing paper and other media, storage media such as DVDs, CDs, and memory cards, and other objects that are used in electronic instruments.